Abstract
Cellulose, calcium sulphate dihydrate and silica gel, all of them hydrophilic, are naturally abundant in Brazil and, in addition, find a great number of applications. Silica is used in the tire industry, dentifrice, paints and inks, medicines, Portland cement concrete, etc. Gypsum, or calcium sulphate dihydrate, is been extensively used as a building material because of its recyclable and…